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View Full Version : Not a clue, several objects 18mm thick and of varying sizes?



Wobblybootie
14-10-2014, 07:18 PM
Help or advice needed. I have several objects 18mm thick and of varying sizes. The largest being able to fit into a 48 X 48 inch square, the smallest being 12X3. They are 'organic' in shape so do not lend themselves to being transferred to a digital format by straightforward measuring and inputting into a software package (Solidworks). Could I use the 3 Axis machine (replacing the spindle with some sort of probe) to do it. The object of the exercise is to be able to nest the parts and to be able to scale them to reproduce both larger and smaller copies. All advice gratefully accepted.

Neale
14-10-2014, 07:23 PM
What sort of accuracy needed? Quick way would be to photograph them and use some kind of tracing software to convert to something that your CAM software can accept. There was a long discussion about a very similar problem for cutting panels to line a van - might be an idea to search for that thread as there were lots of ideas.

EddyCurrent
14-10-2014, 07:27 PM
This one.

http://www.mycncuk.com/threads/7823-How-to-get-panels-into-VCarve-Pro-7-5?highlight=lining

Tenson
14-10-2014, 09:28 PM
Some images of what you are trying to reproduce and nest?

There are methods to make 3D scanners with pretty basic stuff. I don't remember the details but I do remember they exist! There was a youtube presentation by a guy who 3D printed many interesting things like false legs who discussed these methods to capture body shapes etc.. I think I remember one method using multiple web-cams and software to merge the data and determine the 3D shape.. others use a laser line scanning bit by bit.

Wobblybootie
15-10-2014, 11:17 AM
No images available at this time but here's a brief description ... imagine a horse, now slice it into 18mm thick pieces running fore and aft or nose to tail. When assembled and finished you end up with a laminated horse. I make Rocking Horses. I normally trace onto Ply then cut out using a Bandsaw and Router. I can and do keep sets as templates but want to store these digitally and machine cut them, saving me space and time. I would also be able to scale them to match the customers requests. If and it's a Massive IF I can afford to build a 5 Axis Machine then I could machine the thing in 2 halves, join and finish as required.

EddyCurrent
15-10-2014, 11:34 AM
Have you seen these, http://www.123dapp.com/catch , also check out the other apps such as this, http://www.123dapp.com/make

Watch the videos

I'm thinking you could capture a completed horse to make a 3D model then slice it up using the 'make' software or there's other software to do this too.

Wobblybootie
15-10-2014, 01:11 PM
Now that's nice!! I like that idea ... off to do some research ...

GEOFFREY
15-10-2014, 11:53 PM
If you are happy to make your models in two halves, surely a three axis machine could do most of this? G,

Wobblybootie
16-10-2014, 01:12 AM
The horse is constructed using a series of ever decreasing 'slices' which are joined and then carved. Yes I could easily join two halves and finish the 'inside' where a 3 Axis system cannot reach by hand. Initially, what I am after is to digitise the templates I have, to enable me to better 'Nest' the parts and cut them out saving me considerable time (and materials). If I can scan a completed 'half' then the router could do it providing there is sufficient Z travel and the Z assembly is kept to a minimum size to clear the 'curves of the body.

Nthkentman
16-10-2014, 03:53 PM
I use Vectric V Carve Pro to design shapes and other stuff in MDF or wood. Usually 2d, but your suggestion of laminating to create a 3d result and then hand finishing would be achievable.
If you were to scan or make a photograph of one of your existing templates you can pull it in to V Carve and using the trace feature you can then make the "Picture" into a new template of any size. Turning that "Shape" outline into vectors for editing is a one click process. (Exportable as a DXF file if you need anyone else to machine it)
Once saved at the dimensions you require it would be easy to make smaller copies using the copy and paste function, then resize using the object size function.
Once you have decided how many to copy the next function would nest them onto the sheet represented in the software.
Obviously readjusting a few vectors where required would be necessary for the various sizes and this will take a little time. But once they are made the cutting out will be a breeze and every time identical.

Have a look at http://forum.vectric.com/ and see if anyone on there has done similar. Very helpful people and the software is a doddle to use and very comprehensive

EddyCurrent
16-10-2014, 06:00 PM
You can also use the open source free software Inkscape to trace an image and output to dxf.

JAZZCNC
16-10-2014, 06:36 PM
Agree with Geoffrey if you can half the finished horse then with a digitising probe you could create a point cloud and mesh together for the finished horse why bother with templates at all.? Then just let the CNC machine do the work.

Even if half is too much Z height for probing or cutting you could slice into managable sizes and probe the edges then piece together very easy.

Can you show a picture of the Templates your talking about.!

Jester
16-10-2014, 07:47 PM
Ive used an xbox 360 kinect camera to scan 3d objects with good results then used slicer ( i think its called to slice it into pieces to carve

Wobblybootie
16-10-2014, 07:59 PM
Hadn't thought of that I guess I'd better checking out the options

EddyCurrent
16-10-2014, 08:22 PM
To keep Z to something sensible I was thinking maybe a fat central spine that would look like a side view of a horse, then add the cnc'd side blocks to it. That way you could do the neck and head in a similar way.

njhussey
16-10-2014, 08:59 PM
You can use Draftsight CAD program (free) to import a jpg as a reference and then on a different layer trace the part. No need to export as a dxf as it's already one so just save...

Wobblybootie
18-10-2014, 10:53 AM
Cheers Guys for loads of ideas on solving my problem. Jazz there's a pic on my Build log of the templates and finished Horse ...